Heading off to school doesn't have to mean leaving your old life behind. With the right mix of Web-based apps, you can take your entire digital life with you--and keep it handy on practically any device you carry.

Cloud apps and online storage services give us constant access to the most important data from all of our devices, and more computing power at our disposal than ever before. Online productivity suites let you work with Microsoft Office documents on your laptop or smartphone, and keep them perpetually available on the Web for easy access. Cloud streaming services make your entire music library available on any device you have handy, or let you tap into an unlimited supply of free tunes from a personalized online radio station. Web-based phone services allow you to call anyone in the world--with video--for next to nothing, and receive calls on any phone. You can even protect your PC with online antivirus apps.

In this article, I'll explain the pros and cons of moving f your digital life to the cloud as you head off to college, and I'll discuss the very best free and paid cloud-based services for storage, security, entertainment, communications, productivity, and more.

Can You Trust the Cloud?

If you're asking whether you can really trust cloud services with your data, we like the way you think. Regarding any online service with a healthy dose of skepticism will generally serve you well. As with most things in the tech world, cloud services make compromises between security and convenience.

To keep your data secure, you want to protect your files from prying eyes while also preventing them from being lost or inadvertently destroyed. Those two objectives aren't mutually exclusive, but can often seem that way.

If your primary concern is making sure that nobody but you ever sees your data, the cloud may not be for you. While most reputable cloud services offer strong guarantees that your data will be heavily encrypted and that no one inside the company has direct access to your files, you can never be 100 percent certain that something won't go wrong.

At the same time, cloud services run on massive, enterprise-grade server farms with tremendous redundancy, so there's little chance your data will be lost accidentally--the risk is far lower than that of keeping data on your own hard drives. Historically, even when cloud providers go belly up, they often keep the servers active long enough for customers to retrieve or delete their files.

Another compromise involves service reliability. If you depend on a Web-based productivity app, it had better be working when you are. A few high-profile Gmail outages have highlighted this concern in the past year, but it's important to note that the likelihood of your PC's broadband service going down is far greater than the likelihood that a major cloud service will suffer significant downtime.

We suggest this: If you're seriously worried that your term paper might suddenly be unavailable for download during finals week, keep a copy on your hard drive. Otherwise, just be sure to use strong passwords on all your accounts.

Cloud Office Suites

Of all the PC software that people use, none is so entrenched on desktops as the office suite. Microsoft Office remains the de facto global standard in document editing, and there's a good chance most of your professors prefer papers submitted in Word's .DOC format.

Although Google was by no means the first company to offer a cloud-based office service, it quickly emerged as the primary cloud-based competitor to Microsoft's hegemony over document creation. At a time when Microsoft seemed to be ignoring the cloud, Google served up three Web-based apps creatively named Documents, Spreadsheets, and Presentations--known collectively as Google Docs.

Google Docs has two main advantages over Office on your desktop: It keeps your documents available on any computer you use (as well as on most smartphones), and it makes sharing and simultaneous editing easy. As a collaboration tool, it's simply awesome.

The primary disadvantage of Google Docs is that, although it claims to support Microsoft Office formats, using the service is the surest way to completely mangle the formatting and layout of any moderately complex Word document, PowerPoint presentation, or Excel spreadsheet. And in our experience, exporting Google Docs documents into their corresponding Microsoft Office formats usually produces disastrously unreadable results.

One of our favorite cloud office suites comes from Zoho. The company offers apps for just about every conceivable productivity task, from word processing to meeting hosting to calendar tracking, presentations, and accounting. It's a positively massive collection of different tools that work well together.

In addition, Zoho features excellent support for Microsoft Office formats, making it a better option than Google Docs for people who need to send their creations to Microsoft Office users. Zoho also provides a software plug-in for Microsoft Office that lets you create and edit documents from your Zoho account using the Office apps on your PC, and automatically save them back to your Zoho storage space. The plug-in is a great compromise for users who prefer working with desktop apps but want the convenience and collaboration benefits of cloud tools. Zoho apps are free for personal use, which is great for students.

Microsoft's Office Web Apps are simplified versions of their desktop counterparts.It probably goes without saying that nobody supports Microsoft Office formats as well as Microsoft itself does. With the launch ofOffice Web Apps alongside--and integrated into--Office 2010, Microsoft has effectively filled the void that its earlier desktop apps left open for Google and Zoho.

Microsoft's current Web Apps lineup includes online versions of Word, Excel, and PowerPoint (along with the note-taking app OneNote). All three replicate the look and feel of their corresponding desktop applications, sporting somewhat simplified versions of each app's familiar menus, so making the leap from the desktop to the Web shouldn't induce vertigo in even the most devoted desktop-app fan.

The Web Apps save all of their files to Microsoft's cloud-storage service, SkyDrive, where you can set sharing permissions on files, invite people to view and edit your documents, and even collaborate on shared documents simultaneously. Note, however, that Office Web Apps are not complete versions of their corresponding desktop apps: Microsoft has simplified the features of the free Web apps to ensure that people still buy its expensive desktop suites. In the company's view, these apps are only a Web extension of the programs in its suites, which range from $150 to $500.

Of the three office options here, we prefer Microsoft's offering for its dependable mix of robust desktop programs and work-from-anywhere cloud apps that provide complete, no-hassle support for the most widely used document formats on earth.

Cloud Storage Services

Your PC's hard drive may have half a terabyte of data on its platters, and you might not remember the last time you backed any of it up. In all likelihood, though, you use only a few gigabytes' worth of files on a regular basis. With a combination of cloud-storage services, you can keep that data backed up and synced among all of your computers automatically, and access your most essential files whenever you want. This is especially cool for students who have a desktop machine in the dorm and a laptop they carry to class.

Cloud-storage services take three distinct approaches: backup, folder syncing, and drop boxes. We've yet to find a single service that offers the perfect blend of all three, but you can easily combine a couple of services, and many great options are free.

Backup

Backing up the entire contents of your hard drive to the cloud comes with a trade-off. What you get is peace of mind--the knowledge that your data is safe in the event that your home vanishes into a black hole that somehow leaves the rest of the planet intact. What you give up is speed: Even with a very fast broadband connection, backing up all of your data can take weeks. Once the initial backup is done, however, regular daily backups of just the newly changed files take almost no time at all, and happen in the background with no effort on your part.

Restoring data can be painless and quick if you just want to recover a recent version of a particular file, but if you ever need to run a total system recovery, it could take days. Fortunately, most cloud-backup services offer the option of mailing you a recovery disc with your backed-up data on it.

My favorite choice for whole-drive backup, mostly for its great pricing, is a service called BackBlaze, which charges $5 monthly or $50 annually for backing up unlimited data on one computer. Competing backup services run as much as $90 a year for a mere 100GB.

Folder Syncing

If you move between two or three computers on a regular basis, having user folders such as Music or Documents synced between them automatically can be helpful. Sync services such as SugarSync and Microsoft Windows Live SkyDrive can sync any folders you designate, no matter where they are on your system.

SugarSync gives you up to 5GB of synced storage for free, which ought to be plenty for a Documents folder containing nothing but Word docs. If you want to include all your photos and videos, however, you'll likely need a lot more capacity. SugarSync obliges with options ranging from $50 a year for 30GB all the way up to $400 annually for 500GB. The service includes support for Windows, Mac, iOS, Android, BlackBerry, and Windows Mobile, so you can access your files from just about any device you own.

Windows Live SkyDrive offers 25GB of synced storage for free, but supports a narrower range of devices. At press time only Windows PCs support SkyDrive folder syncing, though Macs can access shared data by going to the SkyDrive Website. Smartphones, on the other hand, can share only photos (via a mobile browser) with SkyDrive, and have no access to other file types stored there. What SkyDrive does well, however, is share files between your desktop Office programs and Microsoft Office Web Apps.

Drop Boxes

For quick syncing of critical files between multiple systems, it's hard to beat a drop box, which is a simple folder that connects to a cloud service for automatic synchronization. Just put any file in your drop-box folder, or create any subfolder in it, and that item will instantly appear in the corresponding drop-box folder on any computer or mobile device using the same account.

Drop-box services differ from folder-syncing services in that they sync subfolders and files only within a single drop-box folder; they don't allow you to designate any other folders on your drive for syncing.

The best drop-box software around is the aptly named Dropbox, which comes with 2GB of free storage that you can upgrade to as much as 8GB by spamming your friends to try it out. (Good luck, though; most of your friends are probably already using it.) Amazon recently launched Cloud Drive, which looks like a serious contender with 5GB of free storage.

Cloud Music Services

The past decade has seen the emergence of new services--many of them free--that allow you to stream music from the Web, as well as to store your own music files online for easy access from your PC, your TV, or your smartphone.

Music on Demand

Pandora lets you set up personal radio stations that suit your musical tastes.Services such as Pandora and Slacker create personalized radio stations that bring commercial-free music to your PC or smartphone. Most are free, though all reserve certain features (such as mobile access or desktop apps) to paid customers. Of the major services, Pandora is the best choice for users who want free music on their phones or streamed to their TVs via Roku or other cloud-enabled devices. Another option, Grooveshark, provides more customization by letting you search for and play specific songs on demand, but for a fee.

Social media services such as Blip.fm make it easier to share and discover music with friends through integrated Facebook and Twitter support, so you can tell everyone what you're listening to and see recommendations from people whose taste you trust.

Stream Your Own Tunes

What if you already own lots of great music, and you just want to be able to listen to it on any device? Digital music lockers can store your tracks online and stream them to your PCs, phone, and tablet.

Amazon, Google, and Apple have all launched new services to fill this niche. Amazon's Cloud Player, for the Web and Android phones, offers 5GB of free cloud storage via Amazon Cloud Drive for your existing music collection. You can upgrade with options ranging from 20GB for $20 per year up to (for those who have too much money on their hands) a terabyte for $1000 per year. Upload your existing music files to Cloud Drive, and Cloud Player will stream them to your PC over the Web, or to your Android phone via the Amazon MP3 app. Android users also have the option of copying the files to their SD Card to save bandwidth and avoid streaming problems.

Google Music, which is currently free during the invite-only beta period and will likely remain free with a limited amount of storage once it goes public, lets you upload 20,000 tracks from your PC's music collection, and streams them to the Google Music app on your Android phone or tablet.

Likewise, Apple's new iTunes in the Cloud service lets you stream your iTunes library to other machines running iTunes (including iOS devices).

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